Conventional technology is described e.g. here:                1. U.S. 2012/214,416(A1)—Methods And Apparatuses For Communication Between Devices        2. U.S. 2013/265,857(A1)—Device Association        3. U.S. 2009/156,202(A1)—Methods, Apparatus And Systems For Information Exchange Using Portable Electronic Devices        4. U.S. 2007/234,048(A1)—Session Handover Between Terminals        5. U.S. 2013/122,810(A1)—Device Association        6. U.S. 2010/278,345(A1)—Method And Apparatus For Proximity Based Pairing Of Mobile Devices        7. U.S. 2003/212,549(A1)—Wireless Communication Using Sound        8. U.S. Pat. No. 8,275,315(B2)—System And Method For Transmitting Data Over An Audio Communication Link.        
The disclosures of all publications and patent documents mentioned in the specification, and of the publications and patent documents cited therein directly or indirectly, are hereby incorporated by reference. Materiality of such publications and patent documents to patentability is not conceded.